In an optical transport network (OTN), which is a large-capacity wide area photonic network, various client signals in a synchronous digital hierarchy (SDH), the Ethernet (registered trademark), and the like are accommodated and transferred. In recent years, increase in traffic of client signals is remarkable, and accordingly, standardization of the OTN has been advanced so as to cope with increase in speed (e.g., see Non-Patent Document 1). Currently, an OTUCn (Cn represents 100 G×n), which is an OTN technique over 100 G (B100 G, in which G represents gigabits per second), is being studied (e.g., see Non-Patent Document 2). In the OTUCn, a transport capacity of one optical channel is broader than that of a conventional optical channel transport unit (OTU). However, because of an operational speed of an electronic circuit used for a transceiver of an optical signal, it is difficult to enlarge single carrier transport in a band of one optical channel as before to achieve a larger capacity. For this reason, in the OTUCn, a technique for realizing a larger capacity by multicarrier transport using a plurality of optical subcarriers in a band of one optical channel is being studied.